You need a Mac to develop for mac. I need to travel on top of that. I get roughly 4 to 5 hours on Unity Pro on a battery that’s 4 years old which includes building my games on XCode for iPhone. I only get 2hrs on UE4 on new machine and I am not doing any work yet. editor window is simply maximized. I think there is a problem with software. Note this post is not intended to compare products like Windows vs Mac or Unity vs UE4 I need both respectully.
PC Mag rated newer model at 13.4 hrs (what I bought)
I expect at least 4 hours for real world use.